Patent Application
20230260395
The present disclosure relates to a technique to correct a measured position of a vehicle.
In recent years, research and development have been progressing on an on-vehicle system in which a plurality of sensors is installed and sensor data acquired by the plurality of sensors is used.
Further, research and development have been progressing also on a system that receives through a vehicle-to-vehicle communication, sensor data of a sensor installed in another vehicle and uses the received sensor data.
Furthermore, research and development have been progressing also on a system that builds a coalition of data processing between a vehicle and a roadside server, with using a roadside-to-vehicle communication between the vehicle and the roadside server.
Here, a system is considered in which a moving body such as a vehicle or a person transmits each position to a roadside server and the roadside server recognizes the position of each moving body. In such a system, for example, it is possible for the roadside server to notify a vehicle a in advance of a vehicle b and/or a person whose position is not recognized by the vehicle a.
Further, if the vehicle a transmits to the roadside server, a position of the vehicle a together with a position of a vehicle x acquired by the sensor, it is possible for the roadside server to recognize the position of the vehicle x which is not able to transmit own position to the roadside server.
Positional information to be transmitted to the roadside server, by a moving body such as a vehicle or a person may include an error. For this reason, “positions of the same moving body” measured by a plurality of moving bodies may be “consistent with each other”. Alternatively, “positions of the same moving body” measured by the plurality of moving bodies may “not” be consistent with each other.
That is, a situation may occur where the position of the vehicle a measured by the vehicle a is consistent with the position of the vehicle a measured by the vehicle b, but the position of a vehicle c measured by the vehicle a is not consistent with the position of the vehicle c measured by the vehicle b.
In such a situation, it is necessary to determine whether “consistent positions” are correct or “non-consistent positions” are correct. When “consistent positions” are correct, it is also necessary to determine how to correct “non-consistent positions”.
As a technique to perform correction based on a plurality of measurement results, there is a technique described in Patent Literature 1.
In Patent Literature 1, a vehicle α measures own position and acquires positional information of the vehicle α measured by a surrounding vehicle β. Then, the vehicle α calculates a range of the vehicle α, from an error between the measured position of the vehicle α measured by the vehicle α and the measured position of the vehicle α acquired from the vehicle β. The vehicle α performs the same process on a plurality of surrounding vehicles. Then, the vehicle α corrects the position of the vehicle α so that the position of the vehicle α is in an overlapping range acquired after the same process has been repeated on the plurality of surrounding vehicles.
In the technique of Patent Literature 1, the vehicle α is not able to correct the position unless the vehicle α repeats a plurality of times to receive a measured position from a surrounding vehicle and repeats a plurality of times to collate the measured position from the surrounding vehicle with the measured position by the vehicle α.
For this reason, the technique of Patent Literature 1 has a problem in that it takes time to correct the position.
One of the main aims of the present disclosure is to solve such a problem. More specifically, the present disclosure mainly aims to correct a position in a short time.
A correction data generation device according to the present disclosure includes:
a reception unit to receive from each moving body among a plurality of moving bodies, moving body data indicating a measured position of each moving body which is a position of each moving body measured at each moving body and may include an error, and indicating a measured position of a surrounding object of each moving body which is a position of the surrounding object of each moving body measured at each moving body and may include an error;
a correction data generation unit to generate for each moving body, correction data for correcting the error that may be included in the measured position of each moving body, with using measured positions of the plurality of moving bodies and measured positions of surrounding objects of the plurality of moving bodies indicated in a plurality of moving body data received from the plurality of moving bodies; and
a transmission unit to transmit to each moving body, the correction data for each moving body generated by the correction data generation unit.
According to the present disclosure, it is possible to correct a position in a short time.
Hereinafter, embodiments will be described with reference to the drawings.
In the following description of the embodiments and the drawings, parts assigned the same reference numerals indicate the same parts or corresponding parts.
The position correction system 500 according to the present embodiment includes a correction data generation device 100, an on-vehicle device A 200a, and an on-vehicle device B 200b.
The on-vehicle device A 200a is mounted on a vehicle A 300a. The on-vehicle device B 200b is mounted on a vehicle B 300b. It is assumed that there is no on-vehicle device mounted on a vehicle C 300c and a vehicle D 300d.
Each of the vehicle A 300a, the vehicle B 300b, the vehicle C 300c, the vehicle D 300d, and a pedestrian 400 is a moving body.
Further, each of the vehicle B 300b, the vehicle C 300c, the vehicle D 300d, and the pedestrian 400 which is a moving body existing in the surrounding of the vehicle A 300a, is equivalent to a surrounding object of the vehicle A 300a. Similarly, each of the vehicle A 300a, the vehicle C 300c, the vehicle D 300d, and the pedestrian 400 which is a moving body existing in the surrounding of the vehicle B 300b is equivalent to a surrounding object of the vehicle B 300b.
In the following, when it is not necessary to distinguish between each of the vehicle A 300a, the vehicle B 300b, the vehicle C 300c, the vehicle D 300d, and a vehicle not illustrated in
Further, when it is not necessary to distinguish between the on-vehicle device A 200a and the on-vehicle device B 200b, they are collectively referred to as an on-vehicle device 200.
The on-vehicle device A 200a measures a position of the vehicle A 300a. Further, the on-vehicle device A 200a measures positions of the surrounding objects of the vehicle A 300a. The on-vehicle device A 200a measures a speed of the vehicle A 300a and speeds of the surrounding objects.
The on-vehicle device A 200a transmits a measurement result to the correction data generation device 100, as vehicle data A. The vehicle data A is equivalent to moving body data. The measurement result of the on-vehicle device A 200a includes the measured position of the vehicle A 300a, the measured positions of the surrounding objects of the vehicle A 300a, the measured speed of the vehicle A 300a, and the measured speeds of the surrounding objects.
The measurement result of the on-vehicle device A 200a may include a measurement error.
In the present embodiment, it is assumed that the on-vehicle device A 200a is able to measure only the positions and speeds of the vehicle B 300b, the vehicle C 300c, and the pedestrian among the surrounding objects.
Similarly, the on-vehicle device B 200b measures a position of the vehicle B 300b. Further, the on-vehicle device B 200b measures positions of the surrounding objects of the vehicle B 300b. The on-vehicle device B 200b measures a speed of the vehicle B 300b and speeds of the surrounding objects. The on-vehicle device B 200b may not measure the speed of the vehicle B 300b. Here, it is assumed that the on-vehicle device B 200b measures the speed of the vehicle B 300b.
The on-vehicle device B 200b transmits a measurement result to the correction data generation device 100, as vehicle data B. The vehicle data B is equivalent to moving body data. The measurement result of the on-vehicle device B 200b includes the measured position of the vehicle B 300b, the measured positions of the surrounding objects of the vehicle B 300b, the measured speed of the vehicle B 300b, and the measured speeds of the surrounding objects.
The measurement result of the on-vehicle device B 200b may include a measurement error.
In the present embodiment, it is assumed that the on-vehicle device B 200b is able to measure only the positions and speeds of the vehicle A 300a and the vehicle D 300d among the surrounding objects.
An operation procedure of the on-vehicle device 200 is equivalent to an error correction method. Further, a program that implements operation of the on-vehicle device 200 is equivalent to an error correction program.
The correction data generation device 100 is, for example, a roadside server device arranged on a side of a roadway on which the vehicle 300 travels. The correction data generation device 100 may be a server device other than the roadside server device.
An operation procedure of the correction data generation device 100 is equivalent to a correction data generation method. Further, a program that implements operation of the correction data generation device 100 is equivalent to a correction data generation program.
The correction data generation device 100 receives the vehicle data A and the vehicle data B.
Then, the correction data generation device 100 generates correction data for each of the vehicle A 300a and the vehicle B 300b, with using the measurement result included in the vehicle data A and the measurement result included in the vehicle data B.
The correction data (referred to as correction data A) for the vehicle A 300a is data for correcting the measurement error included in the measurement result of the on-vehicle device A 200a. That is, the correction data A is data for correcting the measurement error possibly included in the measured position of the vehicle A 300a and the measurement errors possibly included in the measured positions of the surrounding objects of the vehicle A 300a.
The correction data (referred to as correction data B) for the vehicle B 300b is data for correcting the measurement error included in the measurement result of the on-vehicle device B 200b. That is, the correction data B is data for correcting the measurement error possibly included in the measured position of the vehicle B 300b and the measurement errors possibly included in the measured positions of the surrounding objects of the vehicle B 300b.
Then, the correction data generation device 100 transmits the correction data A to the on-vehicle device A 200a and transmits the correction data B to the on-vehicle device B 200b.
The on-vehicle device A 200a receives the correction data A. Then, the on-vehicle device A 200a corrects a positioning error included in the measured position of the vehicle A 300a, with using the correction data A. In addition, the on-vehicle device A 200a corrects positioning errors included in the measured positions of the surrounding objects of the vehicle A 300a, with using the correction data A.
Similarly, the on-vehicle device B 200b receives the correction data B. Then, the on-vehicle device B 200b corrects a positioning error included in the measured position of the vehicle B 300b, with using the correction data B. In addition, the on-vehicle device B 200b corrects positioning errors included in the measured positions of the surrounding objects of the vehicle B 300b, with using the correction data B.
Before describing detailed configurations of the correction data generation device 100 and the on-vehicle device 200, the outline of the processing procedure of the position correction system 500 will be described.
The correction data generation device 100 receives a plurality of vehicle data from a plurality of vehicles 300. The vehicle data received by the correction data generation device 100 includes the vehicle data A and the vehicle data B.
In the following, one or more pieces of vehicle data other than the vehicle data A and the vehicle data B are collectively referred to as vehicle data N (not illustrated in
Further, the vehicle 300 from which the vehicle data is transmitted is also referred to as a transmission source vehicle 300.
As described above, the vehicle data A is data transmitted from the on-vehicle device A 200a of the vehicle A 300a and that indicates the measurement result of the on-vehicle device A 200a. The vehicle data A indicates the measured position of the vehicle A 300a which is the transmission source vehicle 300. Further, the vehicle data A indicates a position of a vehicle X1, a position of a vehicle X2, and a position of a pedestrian, as the measured positions of the surrounding objects. The vehicle X1 is the vehicle C 300c in
It is assumed that the correction data generation device 100 is able to recognize that the vehicle A 300a indicated in the vehicle data A is the transmission source vehicle 300 of the vehicle data A.
As described above, the vehicle data B is data transmitted from the on-vehicle device B 200b of the vehicle B 300b and that indicates the measurement result of the on-vehicle device B 200b. The vehicle data B indicates the measured position of the vehicle B 300b which is the transmission source vehicle 300. Further, the vehicle data B indicates a position of a vehicle Y1 and a position of a vehicle Y2, as the measured positions of the surrounding objects. The vehicle Y1 is the vehicle A 300a in
It is assumed that the correction data generation device 100 is able to recognize that the vehicle B 300b indicated in the vehicle data B is the transmission source vehicle 300 of the vehicle data B.
Although an illustration of the vehicle data N is omitted, it is the same data as the vehicle data A and the vehicle data B described above.
Each of the transmission source vehicles 300 measures the position of the transmission source vehicle 300 and the positions of the surrounding objects at an individual timing. The vehicle data indicates a measurement time at the transmission source vehicle 300.
As illustrated in
In this way, a measurement is not always taken at the same time in each transmission source vehicle 300, so that there may be a difference in the measurement times between pieces of vehicle data.
The correction data generation device 100 removes such a difference in the measurement times. To remove the difference in the measurement times, the correction data generation device 100 sets a time (hereinafter referred to as a reference time) which is a time after the measurement times of a plurality of transmission source vehicles 300 and commonly applied to the plurality of transmission source vehicles 300. Then, the correction data generation device 100 calculates a predicted position of each transmission source vehicle 300 at the reference time and predicted positions of the surrounding objects of each transmission source vehicle 300 at the reference time.
Specifically, the correction data generation device 100 sets as the reference time, a latest measurement time among the measurement times of the plurality of received vehicle data. Then, the correction data generation device 100 predicts the position of each transmission source vehicle 300 at the reference time and the positions of the surrounding objects of each transmission source vehicle 300 at the reference time. When the measurement time is identical with the reference time, the correction data generation device 100 uses the measured position indicated in the vehicle data, as the predicted position.
In an example of
That is, based on the measured position and the measured speed of the vehicle A 300a indicated in the vehicle data A, the correction data generation device 100 calculates the predicted position of the vehicle A 300a at the time 3. Further, based on the measured position and the measured speed of each surrounding object (the vehicle X1, the vehicle X2, or the pedestrian), the correction data generation device 100 calculates the predicted position of each surrounding object at the time t3. Data that indicates the predicted positions of the vehicle A 300a and each surrounding object at the time t3 is referred to as prediction data A.
Similarly, the correction data generation device 100 calculates also for the vehicle data B, the predicted position of the vehicle B 300b and each surrounding object at the time t3. Data that indicates the predicted positions of the vehicle B 300b and each surrounding object at the time t3 is referred to as prediction data B.
Further, similarly, the correction data generation device 100 calculates also for the vehicle data N, the predicted position of the vehicle N 300n and each surrounding object at the time t3. Data that indicates the predicted positions of the vehicle N 300n and each surrounding object at the time t3 is referred to as prediction data N (not illustrated in
Next, the correction data generation device 100 generates integrated data by integrating the prediction data A, the prediction data B, and the prediction data N.
In the integrated data of
The correction data generation device 100 analyzes a distribution of the predicted positions acquired by the integration and calculates a position at which the transmission source vehicle 300 is estimated to be located at the reference time t3, as an estimated position of the transmission source vehicle 300. In the example of
Further, the correction data generation device 100 calculates positions at which the surrounding objects are estimated to be located at the reference time t3, as estimated positions of the surrounding objects.
Next, the correction data generation device 100 generates the correction data for each of the transmission source vehicles 300, with using the estimated position of the transmission source vehicle 300 and the estimated positions of the surrounding objects. That is, the correction data generation device 100 generates the correction data A which is the correction data for the vehicle A 300a, with using the estimated position of the vehicle A 300a and the estimated positions of the surrounding objects. Further, the correction data generation device 100 generates the correction data B which is the correction data for the vehicle B 300b, with using the estimated position of the vehicle B 300b and the estimated positions of the surrounding objects. Furthermore, the correction data generation device 100 generates correction data N (not illustrated in
For example, the correction data A indicates correction values (δ11 to δ14) for each of the vehicle X1, the vehicle A 300a, the pedestrian, and the vehicle X2 indicated in the vehicle data A. Similarly, the correction data B indicates correction values (δ21 to δ23) for each of the vehicle Y1, the vehicle B 300b, and the vehicle Y2 indicated in the vehicle data B.
The correction values indicated in the correction data eliminate the measurement errors at each on-vehicle device 200. That is, the correction value indicated in the correction data is equivalent to the measurement error at the measurement time of each on-vehicle device 200.
After that, the correction data generation device 100 transmits the correction data A to the vehicle A 300a. Further, the correction data generation device 100 transmits the correction data B to the vehicle B 300b. Furthermore, the correction data generation device 100 transmits the correction data N to the vehicle N 300n.
Next, a functional configuration example and a hardware configuration example of the on-vehicle device 200 according to the present embodiment will be described.
The on-vehicle device 200 is a computer. An operation procedure of the on-vehicle device 200 is equivalent to an error correction method. Further, a program that implements operation of the on-vehicle device 200 is equivalent to an error correction program.
As illustrated in
Further, as illustrated in
The auxiliary storage device 803 stores programs that implement functions of the vehicle position measurement unit 201, the surrounding object position measurement unit 202, the transmission unit 203, the reception unit 204, and the correction unit 205.
These programs are loaded from the auxiliary storage device 803 into the main storage device 802. Then, the processor 801 executes these programs and performs operation of the vehicle position measurement unit 201, the surrounding object position measurement unit 202, the transmission unit 203, the reception unit 204, and the correction unit 205 to be described below.
In
The vehicle position measurement unit 201 measures the position of the vehicle 300 with using, for example, a positioning signal from a Global Positioning System (GPS) satellite. Further, the vehicle position measurement unit 201 measures the speed with using, for example, a difference in measured positions in a unit time.
Then, the vehicle position measurement unit 201 outputs to the transmission unit 203, the measurement time, and the measured position and the measured speed of the vehicle 300. The measurement time is a time at which the vehicle position measurement unit 201 has measured the position and the speed of the vehicle 300. The vehicle position measurement unit 201 uses a unified time such as GPS time, as the measurement time. That is, an identical time is used in each vehicle 300. In other words, measurement timings may vary among the vehicles 300, but it is considered that there is no time gap among the vehicles 300.
Further, the vehicle position measurement unit 201 outputs the measured position of the vehicle 300 to the correction unit 205.
The vehicle position measurement unit 201 is equivalent to a measurement unit, together with the surrounding object position measurement unit 202 to be described below. Further, a process to be performed by the vehicle position measurement unit 201 is equivalent to a measurement process, together with a process to be performed by the surrounding object position measurement unit 202.
The surrounding object position measurement unit 202 measures the positions and the speeds of the surrounding objects of the vehicle 300. The surrounding object position measurement unit 202 measures the measured positions and the measured speeds at the same measurement time as that of the vehicle position measurement unit 201.
The surrounding object position measurement unit 202 measures the positions and the speeds of the surrounding objects with using, for example, sensor data from a sensor mounted on the vehicle 30). The surrounding object position measurement unit 202 measures, relative positions and relative speeds from the vehicle 300, as the positions and the speeds of the surrounding objects. In the present embodiment, any method is used by the sensor to detect the surrounding objects. In the present embodiment, an example in which the surrounding object position measurement unit 202 measures the speeds of the surrounding objects will be described, but the surrounding object position measurement unit 202 does not need to measure the speeds of the surrounding objects.
The surrounding object position measurement unit 202 outputs the measured positions and the measured speeds of the surrounding objects to the transmission unit 203. Further, the surrounding object position measurement unit 202 outputs the measured positions of the surrounding objects to the correction unit 205.
The surrounding object position measurement unit 202 is equivalent to the measurement unit, together with the vehicle position measurement unit 201. Further, the process performed by the surrounding object position measurement unit 202 is equivalent to the measurement process, together with the process performed by the vehicle position measurement unit 201.
The transmission unit 203 transmits to the correction data generation device 100, the measurement time, the measured position and the measured speed of the vehicle 300, as well as the measured positions and the measured speeds of the surrounding objects, as the vehicle data. The transmission unit 203 assigns an identifier of the on-vehicle device 200 to the vehicle data and transmits the vehicle data to the correction data generation device 100. It is conceivable to use a unique number (for example, a Media Access Control (MAC) address) of the communication device 804, as the identifier.
A process performed by the transmission unit 203 is equivalent to a transmission process.
The reception unit 204 receives the correction data from the correction data generation device 100.
Then, the reception unit 204 outputs the received correction data to the correction unit 205.
A process performed by the reception unit 204 is equivalent to a reception process.
The correction unit 205 corrects the measured position of the vehicle 300 acquired from the vehicle position measurement unit 201 and the measured positions of the surrounding objects acquired from the surrounding object position measurement unit 202, with using the correction values indicated in the correction data.
Next, a functional configuration example and a hardware configuration example of the correction data generation device 100 according to the present embodiment will be described.
The correction data generation device 100 is a computer. An operation procedure of the correction data generation device 100 is equivalent to a correction data generation method. Further, a program that implements operation of the correction data generation device 100 is equivalent to a correction data generation program.
As illustrated in
Further, as illustrated in
The auxiliary storage device 903 stores programs that implement functions of the reception unit 101, the correction data generation unit 102, and the transmission unit 103.
These programs are loaded from the auxiliary storage device 903 into the main storage device 902. Then, the processor 901 executes these programs and performs operation of the reception unit 101, the correction data generation unit 102, and the transmission unit 103 to be described below.
In
The reception unit 101 outputs the received vehicle data to the correction data generation unit 102.
A process performed by the reception unit 101 is equivalent to a reception process.
The correction data generation unit 102 acquires the vehicle data from the reception unit 101. Then, the correction data generation unit 102 generates the correction data for each transmission source vehicle 300, with using the plurality of vehicle data from the plurality of on-vehicle devices 200. The correction data generation unit 102 outputs the generated correction data to the transmission unit 103.
A process performed by the correction data generation unit 102 is equivalent to a correction data generation process.
The transmission unit 103 acquires from the correction data generation unit 102, the correction data for each of the transmission source vehicles 300. Then, the transmission unit 103 transmits the corresponding correction data to the on-vehicle device 200 of the transmission source vehicle 300.
A process performed by the transmission unit 103 is equivalent to a transmission process.
Next, an operation example of the on-vehicle device 200 will be described with reference to
First,
When the measurement timing for the position and the speed arrives, the vehicle position measurement unit 201 measures the position and the speed of the vehicle 300 (step S201).
As described above, the vehicle position measurement unit 201 measures the position of the vehicle 300 with using a positioning signal from a GPS satellite. Further, the vehicle position measurement unit 201 measures the speed with using, for example, a difference in measured positions in a unit time.
The vehicle position measurement unit 201 may measure the position and the speed of the vehicle 300, with using the correction value acquired by the correction unit 205 for the measured position of the vehicle 300 at a previous measurement timing.
The surrounding object position measurement unit 202 measures the positions and the speeds of the surrounding objects with using for example, sensor data from a sensor mounted on the vehicle 300 (step S202). The surrounding object position measurement unit 202 measures the relative positions and the relative speeds of the vehicle 300, as the positions and the speeds of the surrounding objects.
The surrounding object position measurement unit 202 may measure the positions and the speeds of the surrounding objects, with using the correction values acquired by the correction unit 205 for the measured positions of the surrounding objects at a previous measurement timing.
In
Next, the transmission unit 203 transmits the vehicle data to the correction data generation device 100 (step S203).
As described above, the transmission unit 203 transmits to the correction data generation device 100, the measurement time, the measured position and the measured speed of the vehicle 300, as well as the measured positions and the measured speeds of the surrounding objects, as the vehicle data. Further, the transmission unit 203 assigns the identifier of the on-vehicle device 200 to the vehicle data and transmits the vehicle data to the correction data generation device 100.
In the present embodiment, it is assumed that the transmission unit 203 has already acquired a communication address of the correction data generation device 100. Any method is used by the transmission unit 203 to acquire the communication address of the correction data generation device 100.
After transmitting the vehicle data, the on-vehicle device 200 waits for the arrival of a next measurement timing (step S204) and starts the processes from step S201 onwards at a time when the next measurement timing arrives.
Next,
When the reception unit 204 receives the correction data from the correction data generation device 100 (YES in step S211), the correction unit 205 corrects the position of the vehicle 300 and the positions of the surrounding objects with using the correction data (step S212).
As illustrated in
Next, with reference to
When the reception unit 101 receives the vehicle data from the vehicle 300 (YES in step S101), the reception unit 101 stores the received vehicle data into the auxiliary storage device 903 (step S102).
Then, the reception unit 101 waits to receive the vehicle data until a certain period of time elapses from a reception time of the first received vehicle data.
After the certain period of time has elapsed from the reception time of the first received vehicle data (YES in step S103), the correction data generation unit 102 sets the reference time (step S104).
Specifically, the correction data generation unit 102 sets a latest measurement time among the measurement times of the vehicle data stored in the auxiliary storage device 903, as the reference time.
Next, the correction data generation unit 102 calculates the predicted position of the transmission source vehicle 300 at the reference time and the predicted positions of the surrounding objects at the reference time (step S105).
The correction data generation unit 102 calculates the predicted position of the transmission source vehicle 300 at the reference time and predicted positions of the surrounding objects at the reference time, with using the measured position and the measured speed of the transmission source vehicle 300 as well as the measured positions and the measured speeds of the surrounding objects.
The correction data generation unit 102 performs a pre-prediction process by means of a Kalman filter and calculates the predicted position of the transmission source vehicle 300 at the reference time and the predicted positions of the surrounding objects at the reference time.
Here, an example will be described in which the correction data generation unit 102 calculates the predicted position of the vehicle A 300a at the reference time t3. It is assumed that the measurement time of the vehicle data received from the vehicle A 300a is the time t1. It is assumed that the auxiliary storage device 903 stores the measured positions and the predicted positions of the vehicle A 300a at past measurement times (time to, time (t−1), and the like).
The correction data generation unit 102 calculates an error between a past measured position and the predicted position calculated to correspond to that measured position. For example, the correction data generation unit 102 calculates an error between the measured position of the vehicle A 300a at the measurement time t0 and the predicted position calculated to correspond to that measured position. Further, the correction data generation unit 102 calculates an error between the measured position of the vehicle A 300a at the time t(−1) and the predicted position calculated to correspond to that measured position. Then, the correction data generation unit 102 calculates by means of the Kalman filter, the predicted position of the vehicle A 300a at the time t2 and the predicted position of the vehicle A 300a at the time t3, with using the calculated errors as well as the measured position and the measured speed of the vehicle A 300a at the measurement time t1.
In the same way, the correction data generation unit 102 calculates the predicted positions of the surrounding objects of the vehicle A 300a at the reference time 3.
The details of the Kalman filter are described in the following reference.
When the speeds of the surrounding objects are not measured by the vehicle 300, the correction data generation unit 102 determines the predicted position of each surrounding object at the reference time, from the predicted position of the transmission source vehicle 300 (for example, the vehicle A 300a) at the reference time and the relative position of each surrounding object from the transmission source vehicle 300 (for example, the vehicle A 300a) at the measurement time (for example, the time t1).
Next, the correction data generation unit 102 calculates the estimated position of the transmission source vehicle 300 at the reference time (step S106).
Specifically, the correction data generation unit 102 integrates a plurality of prediction data. Then, the correction data generation unit 102 analyzes the distribution of the predicted positions acquired by the integration and calculates a position (an estimated position) at which the transmission source vehicle 300 is estimated to be located at the reference time.
There is a case where the transmission source vehicle 300 is detected as a surrounding object of another vehicle. In the example of
Further, due to the measurement errors and the prediction errors, even a plurality of predicted positions of the same transmission source vehicle 30) may not be consistent with each other. That is, in the example of
Further, the transmission source vehicle 300 and a surrounding object of another vehicle 300 are not related with each other in ID information or the like. For this reason, the correction data generation unit 102 needs to calculate from the distribution of the predicted positions, the estimated position of the transmission source vehicle 300.
A calculation procedure of the predicted position of the transmission source vehicle 300 will be described below.
In the following, each predicted position acquired by integrating pieces of prediction data is referred to as Pi. The predicted position Pi includes both of the predicted position of the transmission source vehicle 300 and the predicted positions of the surrounding objects. Further, among the predicted positions Pi, the predicted position of the transmission source vehicle 300 is referred to as Po_i.
First, the correction data generation unit 102 groups the predicted positions mutually located within a first distance σ1 in the distribution of the predicted positions Pi. The predicted positions included in each group acquired by grouping are referred to as GPi.
The size of the first distance σ1 varies depending on the moving bodies. In the present embodiment, in order to find the estimated position of the vehicle 300, the first distance σ1 is set to about 2m in consideration of the length and width of the vehicle. When finding the estimated position of another type of moving body, the first distance σ1 is determined in consideration of the size of the target moving body.
Unless each of the predicted positions GPi is of the same vehicle, a plurality of predicted positions GPi is considered not to come close within the first distance σ1. In other words, the plurality of predicted positions GPi within the first distance σ1 is considered to be the predicted positions of the same vehicle. In the example of
Next, the correction data generation unit 102 performs the following processes 111 to 119 for each group.
First, the correction data generation unit 102 selects one unselected group from a plurality of groups (process 111).
Then, the correction data generation unit 102 determines whether or not the predicted position Po_i of the transmission source vehicle 300 is included in the predicted positions GPi included in the selected group (process 112).
When the predicted position Po_i of the transmission source vehicle 300 is included in the selected group, the correction data generation unit 102 calculates a mean position GPi_a and a positional standard deviation GPi_sd of the predicted positions GPi excluding the predicted position Po_i of the transmission source vehicle 300 (process 113). A group that includes the predicted position Po_i is equivalent to a correction target group. Further, the mean position GPi_a is equivalent to a first mean position.
It is assumed that the predicted positions Po_i of the plurality of transmission source vehicles 300 are not included in the predicted positions GPi. As described above, the length and width of the vehicle are reflected in the first distance σ1, so that it is unlikely that the predicted positions Po_i of the plurality of transmission source vehicles 300 are included in the same group.
Next, the correction data generation unit 102 determines a second distance σ2 (process 114). Specifically, the correction data generation unit 102 sets ±2*GPi_sd as the second distance σ2, with using the positional standard deviation GPi_sd.
Next, the correction data generation unit 102 selects the predicted positions GPi located within the second distance σ2 from the mean position GPi_a (process 115). That is, the correction data generation unit 102 selects the predicted positions located within GPi_a±2*GPi_sd.
Next, the correction data generation unit 102 calculates the mean position of the predicted positions GPi (including the predicted position GPi_o of the transmission source vehicle 300) selected in the process 115 (process 116). The mean position calculated in the process 116 is equivalent to a second mean position.
Then, the correction data generation unit 102 uses the mean position calculated in the process 116, as the estimated position of the transmission source vehicle 300 (process 117).
In the process 112, when the predicted position Po_i of the transmission source vehicle 300 is not included in the selected group, the correction data generation unit 102 calculates the mean position and the positional standard deviation of all of the predicted positions GPi, and estimates the position by performing the same processes described above (process 118).
Further, the correction data generation unit 102 stores the estimated position acquired in the process 117 and the estimated position acquired in the process 118 into the auxiliary storage device 903, together with the reference time (process 119).
After completing the process 119 for all groups, as illustrated in
Specifically, the correction data generation unit 102 extracts a difference between the predicted position of the transmission source vehicle 300 calculated in step S105 and the estimated position of the transmission source vehicle 300 calculated in step S106 (process 117). Further, the correction data generation unit 102 extracts a difference between the predicted position of each surrounding object calculated in step S105 and the estimated position of each surrounding object calculated in step S106 (process 118).
Next, the correction data generation unit 102 adjusts the positional difference acquired in step S107, with using a time difference (step S108).
The positional difference acquired in step S107 is a difference between the predicted position and the estimated position at the reference time. The measured position indicated in the vehicle data transmitted from the transmission source vehicle 300 is a position at the measurement time. For this reason, the correction data generation unit 102 adjusts the positional difference acquired in step S107 so as to reflect the difference between the measurement time and the reference time.
Specifically, the correction data generation unit 102 performs the following process.
Here, it is assumed that the position of the transmission source vehicle 300 at a measurement time ti indicated in the vehicle data is referred to as Psrc_i.
Further, the predicted position (the predicted position calculated in step S105) of the transmission source vehicle 300 at the reference time t is referred to as Ppre_i.
Further, the estimated position of the transmission source vehicle 300 calculated in step S106 is referred to as Presult_i.
Further, the positional difference of the transmission source vehicle 300 acquired in step S107 is referred to as (Presult_i−Ppre_i).
In step S108, the correction data generation unit 102 adjusts the positional difference with using the time difference by means of “(Presult_i−Ppre_i)*(1−(t−ti)/cycle)”. Note that “cycle” is a waiting time in step S103.
The correction data generation unit 102 performs the same process for each surrounding object.
Values acquired in step S108 are the correction values and equivalent to δ11 to δ14 and δ21 to δ23 indicated in
Next, the correction data generation unit 102 generates the correction data for each transmission source vehicle 300 with using the values acquired in step S108 (step S109).
Then, the transmission unit 103 transmits for each transmission source vehicle 300, the correction data generated in step S10) (step S110).
After that, as illustrated in
In the above, the example has been described in which the correction data generation unit 102 generates the correction data for correcting the measured position of the transmission source vehicle 300 and the measured positions of the surrounding objects. Instead of this, the correction data generation unit 102 may generate the correction data for correcting only the measured position of the transmission source vehicle 300. In this case, the on-vehicle device 200 corrects only the measured position of the vehicle 300 with using the correction data.
Further, in the above, the vehicle 300 has been described as an example of the moving body. However, the position correction system 500 according to the present embodiment is able to be applied to moving bodies other than the vehicle, such as a pedestrian and a robot.
As described above, according to the present embodiment, it is possible to correct a position in a short time.
As described above, in the technique of Patent Literature 1, the vehicle α is not able to correct the position unless the vehicle α repeats a plurality of times to receive a measured position from a surrounding vehicle and repeats a plurality of times to collate the measured positions from the surrounding vehicle with the measured position by the vehicle α. For this reason, in the technique of Patent Literature 1, it takes time to correct the position.
In the present embodiment, each on-vehicle device 200 is able to correct the position only by transmitting the vehicle data and receiving the correction data. That is, according to the present embodiment, each on-vehicle device 200 is able to correct the position without a plurality of times of communications and a plurality of times of collations.
Further, in the technique of Patent Literature 1, the vehicle α is not able to correct the position unless there is a surrounding vehicle that is able to measure the position of the vehicle α.
In the present embodiment, even when two vehicles are not able to mutually measure the position of the other, the two vehicles are able to correct each position if another vehicle is able to measure the positions of the two vehicles. For example, it is assumed that a vehicle P is in a state of not being able to measure a position of a vehicle Q and the vehicle Q is in a state of not being able to measure a position of the vehicle P. Further, it is assumed that a vehicle R is in a state of being able to measure the position of the vehicle P and the position of the vehicle Q. In this case, the vehicle P transmits the measured position of the vehicle P to the correction data generation device 100. Further, the vehicle Q transmits the measured position of the vehicle Q to the correction data generation device 100. Further, the vehicle R transmits to the correction data generation device 100, the measured position of the vehicle P and the measured position of the vehicle Q, as the measured positions of the surrounding objects. The correction data generation device 100 is able to transmit to the vehicle P, the correction data for correcting the measured position of the vehicle P, with using the measured position of the vehicle P from the vehicle P and the measured position of the surrounding object (the measured position of the vehicle P) from the vehicle R. Similarly, the correction data generation device 100 is able to transmit to the vehicle Q, the correction data for correcting the measured position of the vehicle Q, with using the measured position of the vehicle Q from the vehicle Q and the measured position of the surrounding object (the measured position of the vehicle Q) from the vehicle R.
Further, in the technique of Patent Literature 1, only the position of the vehicle α can be corrected. That is, in the technique of Patent Literature 1, a position of a surrounding object cannot be corrected.
According to the present embodiment, the position of the surrounding object can be also corrected.
Finally, a supplementary description of the hardware configuration of the on-vehicle device 200 and the hardware configuration of the correction data generation device 100 will be given.
The processor 801 illustrated in
The processor 801 is a Central Processing Unit (CPU), a Digital Signal Processor (DSP), or the like.
The main storage device 802 illustrated in
The auxiliary storage device 803 illustrated in
The communication device 804 illustrated in
The communication device 804 is, for example, a communication chip or a Network Interface Card (NIC).
Further, the auxiliary storage device 803 also stores an Operating System (OS).
Then, at least a part of the OS is executed by the processor 801.
While executing at least the part of the OS, the processor 801 executes the programs that implement the functions of the vehicle position measurement unit 201, the surrounding object position measurement unit 202, the transmission unit 203, the reception unit 204, and the correction unit 205.
By the processor 801 executing the OS, task management, memory management, file management, communication control, and the like are performed.
Further, at least one of information, data, a signal vale, and a variable value that indicate results of processes of the vehicle position measurement unit 201, the surrounding object position measurement unit 202, the transmission unit 203, the reception unit 204, and the correction unit 205 is stored in at least one of the main storage device 802, the auxiliary storage device 803, and a register and a cache memory in the processor 801.
Further, the programs that implement the functions of the vehicle position measurement unit 201, the surrounding object position measurement unit 202, the transmission unit 203, the reception unit 204, and the correction unit 205 may be stored in a portable recording medium such as a magnetic disk, a flexible disk, an optical disc, a compact disc, a Blu-ray (registered trademark) disc, or a DVD. Then, the portable recording medium storing the programs that implement the functions of the vehicle position measurement unit 201, the surrounding object position measurement unit 202, the transmission unit 203, the reception unit 204, and the correction unit 205 may be distributed.
Further, the “unit” of each of the vehicle position measurement unit 201, the surrounding object position measurement unit 202, the transmission unit 203, the reception unit 204, and the correction unit 205 may be read as a “circuit”, “step”, “procedure”, “process” or “circuitry”.
Further, the on-vehicle device 200 may be implemented by a processing circuit. The processing circuit is, for example, a logic Integrated Circuit (IC), a Gate Array (GA), an Application Specific Integrated Circuit (ASIC), or a Field-Programmable Gate Array (FPGA).
In this case, each of the vehicle position measurement unit 201, the surrounding object position measurement unit 202, the transmission unit 203, the reception unit 204, and the correction unit 205 is implemented as a part of the processing circuit.
The processor 901 illustrated in
The processor 901 is a CPU, a DSP, or the like.
The main storage device 902 illustrated in
The auxiliary storage device 903 illustrated in
The communication device 904 illustrated in
The communication device 904 is, for example, a communication chip or an NIC.
Further, the auxiliary storage device 903 also stores an Operating System (OS).
Then, at least a part of the OS is executed by the processor 901.
While executing at least the part of the OS, the processor 901 executes the programs that implement the functions of the reception unit 101, the data correction generation unit 102, and the transmission unit 103.
By the processor 901 executing the OS, task management, memory management, file management, communication control, and the like are performed.
Further, at least one of information, data, a signal vale, and a variable value that indicate results of processes of the reception unit 101, the data correction generation unit 102, and the transmission unit 103 is stored in at least one of the main storage device 902, the auxiliary storage device 903, and a register and a cache memory in the processor 901.
Further, the programs that implement the functions of the reception unit 101, the data correction generation unit 102, and the transmission unit 103 may be stored in a portable recording medium such as a magnetic disk, a flexible disk, an optical disc, a compact disc, a Blu-ray (registered trademark) disc, a DVD. Then, the portable recording medium storing the programs that implement the functions of the reception unit 101, the data correction generation unit 102, and the transmission unit 103 may be distributed.
Further, the “unit” of each of the reception unit 101, the data correction generation unit 102, and the transmission unit 103 may be read as a “circuit”, “step”, “procedure”, “process” or “circuitry”.
Further, the correction data generation device 100 may be implemented by a processing circuit. The processing circuit is, for example, a logic IC, a GA, an ASIC, or an FPGA.
In this case, each of the reception unit 101, the correction data generation unit 102, and the transmission unit 103 is implemented as a part of the processing circuit.
Note that, in the present specification, a superordinate concept of the processor and the processing circuit is referred to as “processing circuitry”.
That is, each of the processor and the processing circuit is a specific example of the “processing circuitry”.
100: correction data generation device; 101: reception unit; 102: correction data generation unit; 103: transmission unit; 200: on-vehicle device; 200a: on-vehicle device A; 200b: on-vehicle device B; 201: vehicle position measurement unit; 202: surrounding object position measurement unit; 203: transmission unit; 204: reception unit; 205: correction unit; 300: vehicle; 300a: vehicle A; 300b: vehicle B; 300c: vehicle C; 300d: vehicle D; 300n: vehicle N; 400: pedestrian; 500: position correction system; 801: processor; 802: main storage device; 803: auxiliary storage device; 804: communication device; 901: processor; 902: main storage device; 903: auxiliary storage device; 904: communication device
This application is a Continuation of PCT International Application No. PCT/JP2020/047418, filed on Dec. 18, 2020, all of which is hereby expressly incorporated by reference into the present application.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2020/047418 | Dec 2020 | US |
| Child | 18139009 | US |
